Commutator



A. C. WOOD,

GOMMUTATOR Filed Oct. 2 1924 conditions.

' lever arms, 11., 11, which carry the commu- Spring UNITED STATES'rATr-mr orrlcs";

ANDREW C. WOOD, OF CHICAGO, ILIII'NOIS, ASSIGNOB TO STEWART-WARNERSPEEDOE- ETEB CORPORATION, 01 CHICAGO, ILLINOIS, A CORPORATION 01'VIRGINIA;

v commu'ra'ron.

"Application nledbctober 20, 1924. Serialllo. 744,614.

To all whom it may concem:

Be it known that I, ANDREW citizen of the United States, city ofChicago, in the county of Cook and State of Illinois, have invented.certain new and useful Improvements in Gommutators, of which thefollowing, isa specification, reference being bad to' he accompanyingdrawings, for-min a part thereof.

The purposeo this invention is to provide an improved construction of acommutator for causing the two brushes to be held to the rotor withequal pressure under all It-consists in the elements and features ofconstruction shown and described I as indicated in the claims.

In the drawings:

Figure 1 is an elevation of a commutator embodying this invention shownfully mounted on abracket for carrying it.

' at the line, 2-2, on

the outer side of the brush-carrying arm, the ends of the divergent armsof the spring bein hooked intrf a ertures, 16, in the stem of t e T, allas may clearly understood from Fig. 1.

It will be understood from inspection of the construction as abovedescribed, that both brushes are stressed a ainst the rotor by the sametension, name that of the coiled spring member, 15; that the leverlength ofthe diverging end portions of the spring being the same, andthe lever length of the brush carrying lever arms being the same, andthe link, 16, connecting the spring ends with the lever arms at the samedistance from the fulcrums of the lever arms on the studs, 10, thebrushes willat all times experience equal pressure from the spring forholding them in contact with the rotor.

I claim 1. In a commutator in combination with a. rotor and brush and amount for the same, bruslrcarrymg arms pivoted on the mount, a springattached to the mount and connections therefrom to the brush carryingarms respectively, said connections and their engagement with the brushcarrying arms being adapted for transmitting the stress of the springwith equal advantage of leverage to the brushes respectively.

2. In a. commutator, in combination with the rotor and brushes and amount for the same, lever arms carrying the brushes pivoted on themount, the mount having a pivot stud offset laterally from the diametricplane of the rotor in which the brushes are positioned; a spring coiledabout said stud and having its opposite end portions extended therefromand connected respectively to the two brush carrying lever arms forstressing the brushes oppositely toward the rotor.

3. In the construction defined in claim 1 foregoing, the brush-carryinglever arms being extended at the same side of the d stopped on 0. W001),a residing in the Figure 2 1s a section Fi ure 1.

Iigure 3 is a section at the line, 3 3, on Fi re 1. p

n the drawings A is a bracket mount for the rotor and brushes of thecommutator. B is the rotor element journaled in the mount at a. Themount has projecting at the side at which the rotor is positioned studs,10, 10, affording pivotal support for the tator brushes, 12, 12,respectively, said lever arms bein formedof metal plate folded for theirpivotal engagement with the studs and for clasping and holding thecommutator brushes as seen most clearly in Fig. 1. The mount, B, has athird rigid stud, 13, projecting from the same face as the studs, 10, ina plane intermediate between and parallel to the planes in which thelever arms, 11, '11,- extend for carrying the brushes are positioned,the spring-carrying 110 brushes; this stud, 13, alfords pivotal supportfor a spring member, 15, whichis coiled about said stud as seen in Fig.2, and hasits offset end portions, 16, 16, crossed and extendingdivergently toward the rotor, B, for connection of said divergentlyextending ends respectively with the lever arms, 11, which carry thecommutator brushes, 12, 1-2, respectively. The connection of the armswith the lever arms respectively 'is made by links, 16, 16, each intheform of a T-shaped stamping, the stem of the T being inserted through anaperture, 11, in the arm, 11, the cross head, 16, being said 5 from ingt pivot stud being in a the planes in which their pivots to the b springend portions the coils crossing each heir respective brush a In theconstruction foregoing, the brush-car ing extended at the s 10 metricplane of the brushes are positioned, stud being in a plane in in whichsaid arms extend fro the s ringplane ,intermediate to the brushesrespectively, the spring arms said arms extend from being connected tothe brush-carryin lever hes respectively, arms respectively, by linksengaged wlth the being extended respective springarms an d lever arms,said other for reachspring arms being equal and the link conrmconnections. nections to the lever arms being at equal disdefined inclaim 1, tance from 'thepivots of said lever arms rying lever armsberespectively and from the brushes respecame side of the diatively.

rotor in which the In testimon whereof, I have hereunto set carrying myhand at hicago, Illinois, this 17th day iate the planes of October,1924. 1

in their pivots ANDREW O. WOOD.

